Method for revamping fixed-bed catalytic reformers

ABSTRACT

A method for converting a fixed-bed catalytic reformer unit to a moving-bed unit. The fixed bed reactor is converted to a moving bed reactor that has continuous or intermittent catalyst feeding facilities to allow continuous or intermittent addition of fresh or regenerated catalyst to the catalyst inlet of the moving-bed reactor and continuous or intermittent removal of spent catalyst from the catalyst outlet of the moving-bed reactor. The spent catalyst removed from the reactor is regenerated in a non-integrated regenerator which may be an offsite regenerator, a centrally located on-site regenerator which serves several reforming units or a regenerator shared with a second moving bed unit. The moving-bed reactor, the catalyst feeding facilities and the catalyst recovery facilities are operatively connected between themselves and to existing facilities from the fixed bed unit, such as piping, compression and reformer charge handling and heating. The converted unit is operated at an effective reactor pressure to improve reformate quality and yield over the reformate product from the fixed-bed unit before the conversion.

CROSS REFERENCE TO RELATED APPLICATION

[0001] This application claims priority from U.S. ProvisionalApplication No. 60/421,892, filed 29 Oct. 2002.

FIELD OF THE INVENTION

[0002] The invention relates generally to catalytic reformers. Moreparticularly, the invention relates to an improved method for convertingor revamping high pressure, fixed-bed catalytic reformers to catalyticreformers with continuous, moving-bed reactors.

BACKGROUND OF THE INVENTION

[0003] Catalytic reforming is an established refinery process. It isused for improving the octane quality of hydrocarbon feeds. Generally,reforming refers to the total effect of molecular changes, orhydrocarbon reactions on the hydrocarbon feed, produced by a number ofreactions. Typical reforming reactions include dehydrogenation ofcyclohexanes, dehydroisomerization of alkylcyclopentanes,dehydrocyclization of paraffins and olefins, isomerization ofsubstituted aromatics, and hydrocracking of paraffins. Typical reformingcatalysts are multifunctional catalysts having ahydrogenation-dehydrogenation component dispersed on a porous, inorganicoxide support. The support may typically also contain an acidfunctionality needed for the reforming reactions.

[0004] Reforming reactions are both endothermic and exothermic.Endothermic reactions are typically predominant in the early stages ofreforming. Exothermic reactions are predominant in the later reactionstages. A reforming unit typically comprises a plurality of seriallyconnected reactors with furnaces for supplying additional heat to thereaction stream as it passes from one reactor to the next in order tocompensate for the heat taken up in the overall endothermic character ofthe process. Conventionally, reforming processes have been operated assemiregenerative or cyclic processes using fixed bed reactors orcontinuous processes using moving bed reactors. Proposals have also beenmade for combining fixed and moving bed reactors with the regenerationmode being appropriate to the reactor types used in the hybridconfiguration, so that the fixed bed reactors have retained the fixedbed type regeneration, usually semiregenerative, and the moving bedreactors in the unit have retained the dedicated moving bed regenerator.Units of this hybrid type are disclosed, for example, in U.S. Pat. No.5,190,638; U.S. Pat. No. 5,190,639; U.S. Pat. No. 5,5,196,110; U.S. Pat.No. 5,5,211,838; U.S. Pat. No. 5,5,221,463; U.S. Pat. No. 5,354,451;U.S. Pat. No. 5,368,720 and U.S. Pat. No. 5,417,843. The unit describedin U.S. Pat. No. 5,417,843 uses two trains of fixed bed reactors witheach train having a final moving bed reactor at the end and the movingbed reactors sharing a moving bed regenerator. The unit shown in U.S.Pat. No. 5,190,639 uses two trains of fixed bed units feeding into ashared moving bed reactor with its own dedicated, fully integratedregenerator. Similar hybrid reforming units using combinations of fixedbed and moving bed reactors are described in NPRA Paper No. AM-96-50“IFP Solutions for Revamping Catalytic Reforming Units” (1996 NPRAAnnual Meeting, 17-19 Mar. 1996). U.S. Pat. No. 4,498,973 describes amoving bed reforming unit in which two moving bed reactor stacks share acommon regenerator. UOP has recently announced its CycleX™ Process forincreased hydrogen production from a fixed bed reforming unit by theaddition of a circulating catalyst reactor as the final reactor in thereactor sequence. This reactor is provided with its own heater andregenerator as an expansion of existing assets rather than as asubstitution of them: NPRA Paper AM-03-93.

[0005] In semiregenerative reforming, the entire reforming process unitis operated by gradually and progressively increasing the temperature tocompensate for deactivation of the catalyst caused by coke deposition,until finally the entire unit is shut-down for regeneration andreactivation of the catalyst which is carried out with the catalystremaining in the reactor cases. In cyclic reforming, the reactors areindividually isolated by various piping arrangements. The catalyst isregenerated and then reactivated while the other reactors of the seriesremain on line. A “swing reactor” temporarily replaces the reactor whichis removed from the series for regeneration and reactivation of thecatalyst, which is then put back in the series. In continuous reforming,the reactors are moving-bed reactors with continuous or intermittentaddition and withdrawal of catalyst through which the catalyst movesprogressively before it is passed to a regeneration zone forregeneration and rejuvenation before being returned once again to thereactor. In the regenerator, at least a portion of the deposited coke isburned off and the regenerated catalyst is recycled to the reactor tocontinue the cycle. Commercial continuous reforming units may have thereactors arranged in a side-by-side or in a stacked configuration.Because the continuous mode of operation with its frequent regenerationcan tolerate a higher degree of coke lay-down on the catalyst, it ispossible to operate continuous units at lower pressures than thosenormally used with semi-regenerative and cyclic units in which it isimportant or at least desirable to extend catalyst life betweensuccessive regenerations.

[0006] Environmental concerns have driven the removal of lead from thegasoline pool and the introduction of premium grade, higher octane,lead-free gasoline in Europe and the United States. In response,petroleum refiners have changed the manner in which refinery units arerun to meet the concomitant demand for higher octane, lead-freegasoline. Catalytic reforming units produce a major portion of therefinery gasoline pool and for this reason, improved reforming methodsand units are needed for producing lead-free fuel products with adequateoctane ratings. Reforming can also be an attractive source of hydrogenin the refinery, especially when the sulfur level of fuels must bereduced to meet government regulations.

[0007] Semiregenerative reforming units may be converted to continuousmoving-bed units to take advantage of the improved yield of higheroctane reformate and hydrogen associated with continuous operation butthe conversions which have so far been considered are essentially entireunit replacements which require replacement of all existing vessels andmost of the ancillary equipment as well as installation of an integratedcatalyst regenerator which is one of the most costly items in theconversion. The cost of the regenerator can be as much as about 80percent of the total cost required for the conversion. There is still aneed, therefore, for an improved, less costly revamping method forconverting fixed-bed reformer units to moving-bed reformer units.

SUMMARY OF THE INVENTION

[0008] The present invention relates generally to a technique forconverting fixed-bed, catalytic reformer units to moving-bed catalyticreformer units. The costs of conversion associated with the presentconversion technique will be significantly less than existingconversions partly because the present technique makes use of existingfacilities and does not require dedicated onsite continuous catalystregeneration facilities. Another advantage of the present invention isthat it allows a number of existing moving-bed catalytic reformers toshare a single catalyst regeneration facility, further reducing theinvestment required to convert several fixed-bed units.

[0009] According to the present invention, the technique for convertinga fixed-bed catalytic reformer unit which has at least one fixed-bedcatalytic reformer reactor to a moving bed unit converts the fixed-bedcatalytic reformer reactor to a moving-bed catalytic reformer reactorwhich allows continuous or intermittent addition of fresh or regeneratedcatalyst to its catalyst inlet and continuous or intermittent removal ofspent catalyst from the catalyst outlet of the reactor. The unit isprovided with catalyst feed facilities for continuously orintermittently charging fresh or regenerated catalyst in a continuous orintermittent mode of operation to the moving-bed reactor. In addition,spent catalyst recovery facilities are added for collecting the spentcatalyst, storing it temporarily, and transferring it to a catalystregeneration facility. The moving-bed reactor, the catalyst feedingfacilities and the catalyst recovery facilities are operativelyconnected between themselves and to the existing facilities (piping,ancillary equipment) of the fixed-bed unit that will not requirereplacement.

[0010] The moving-bed reactor is operated at an effective pressure toimprove reformate quality and yield compared to the quality and yieldfrom the fixed-bed unit before the conversion. It is an advantage of thepresent invention that the moving-bed reformer reactors of the convertedunit may be operated at an effective pressure that is sufficiently lowto improve substantially the reformate quality and yield as compared tothe reformate quality and yield obtained from the fixed-bed unit beforeconversion. The pressure is, however, maintained during normal operationat a value which is sufficiently high to allow the use of some of theexisting equipment of the fixed-bed catalytic reformer unit such ascompression, heat exchangers and furnaces. The use of a higher pressurethan typical for a fully integrated continuous reactor-regenerator isdesirable in that it enables the rate of catalyst flow for regenerationto be reduced (relative to that of an integrated unit) and so relievesthe burden of catalyst handling.

[0011] An effective operating pressure for a converted reformer unit maytypically be substantially lower than the operating reactor pressure ofthe fixed-bed unit. Typically, an effective operating pressure for theconverted reformer unit may be from about 15 to about 70 percent,preferably from about 20 to about 60 percent, and more preferably fromabout 25 to about 50 percent lower than the operating reactor pressureof the fixed-bed unit prior to conversion.

[0012] The present invention may employ an offsite catalyst regenerationfacility. Alternatively, it may employ a community onsite continuouscatalyst regeneration facility, i.e., a continuous catalyst regeneratorthat is shared between more than one reactors. Also, a non-continuousonsite regeneration facility may be used for one or more catalyticreformer units.

[0013] Depending on site economics and other factors, it may bepreferable to use an offsite catalyst regeneration facility.Alternatively, a continuous regeneration facility may be located onsitenear a plurality of converted reformers. Catalyst from the continuousreactors in the reformer units may be transported to the regenerationfacility and, after regeneration, be transferred back to the reformersfor re-use n the reactors. Transfer from the reactors to theregenerators may be continuous, e.g. by suitable transfer devices, forexample, by conveyers, or intermittently, for example, by truck or railcar, depending on the extent of site requirements, proximity of theregenerator and other factors. Another variation would be to use anonsite, non-continuous regeneration facility such as a cyclic typeregenerator that can be used to regenerate catalyst from a plurality ofmoving-bed reformer units.

THE DRAWING

[0014]FIG. 1 shows a continuous moving-bed reforming process built froman existing high pressure fixed-bed reformer unit. Thicker liningindicates new equipment and piping while thinner lining indicatesexisting equipment and piping.

DETAILED DESCRIPTION

[0015] The present invention provides a substantially lower cost optionfor refiners to make significant improvements to the performance andservice factor of existing fixed-bed reformer units. Non-continuous (orfixed-bed) catalytic reformers could be semiregenerative catalyticreformers, swing-reactor (also referred to as cyclic regenerationreformers) catalytic reformers or hybrid systems, all of which areknown.

[0016] The non-continuous catalytic reformer unit may be asemiregenerative unit.

[0017] Semiregenerative units typically contain one or more fixed-bedreactors operating in series with inter-bed heaters to maintainoperating severity as the catalyst deactivates by increasing thereaction temperature. Eventually, a semiregenerative unit is shut downfor catalyst regeneration and reactivation.

[0018] Typically operating conditions for a semiregenerative reformerare:

[0019] pressure: 1035 to 3800 kPag (approx 150 to 550 psig)

[0020] temperature: 425 to 565° C. (approx 800 to 1050° F.)

[0021] space velocity: 0.5 to 3.0 WHW

[0022] A high pressure semiregenerative catalytic reformer can beeffectively converted to operate at a lower effective reactor pressurein the reactors of the converted unit to secure substantial improvementsin reformate quality and yield (relative to the semiregenerative unitprior to conversion) but which does not create an insuperable problem ofcatalyst handling (charge, discharge, transfer, regeneration) onceconversion has taken place. Specifically, the present invention methodallows production of reformate preferably having an octane number offrom 90 to 105, more preferably from 95 to 103, and most preferably from98 to 102. In addition to the improved reformate quality and yieldobtained, an effective reactor pressure, as used in the presentinvention, allows the use of existing facilities such as compressionequipment, heat exchangers, furnaces, piping, drums and pumps.

[0023] This effective pressure is typically lower from the reactorpressure of typical semiregenerative units but also higher than with atypical continuous reactor where there are no similar constraints oncatalyst rate created by handling consdierations. It may range from 345to 2760 kpag (50 to 400 psig), preferably from 690 to 2620 kPag (100 to380 psig), and more preferably from about 1035 to 2415 kPag (150 toabout 350 psig).

[0024] The converted unit will be operated at an effective reactorpressure that provides substantially improved reformate quality andyield compared to existing fixed-bed reforming units. The extent ofreduction in reactor pressure may be limited, if desired, to the extentthat much of the existing compression, furnace, piping, etc., equipmentcan be reused with the new moving-bed reactors. Limiting the extent ofthe pressure reduction also reduces the required catalyst circulationrate (between reactors and regeneration facilities). This isparticularly attractive in a system where the spent catalyst is sentoffsite for regeneration. Typically, a reactor pressure reduction offrom about 25 to about 50% can be realized without having to replacemost of the existing facilities. However, much larger pressurereductions may also be used where it may be attractive under somesite-specific conditions to replace much of the existing facilities.

[0025] Preferably, the fixed-bed reformer unit will converted to amoving-bed reformer reactor that allows continuous addition of freshlyregenerated catalyst to an inlet of the reactor and continuous removalof spent catalyst from an outlet of the reactor. This may be achieved bythe provision of suitable storage for regenerated catalyst or by use ofa regenerator which is shared by two or more reactor trains, e.g. thecatalyst from a converted unit is regenerated in the regenerator of asecond reformer unit in which the regenerator is integrated with the(second) reactor train but not with the first reactor train, i.e. theregenerator for the converted unit is a non-dedicated regenerator. Ashared regenerator may be fully integrated with one reactor train butconstructed so that it has the capacity to regenerate the catalyst fromtwo or more reactors. The non-integrated reactors may be on-site (samerefinery plant) or at remote sites. In this way, the substantial capitalcost of the regenerator is proportionately reduced because of theeconomies of scale associated with regeneration facilities.

[0026] The conversion of a fixed bed (semiregenerative or cyclic)reformer unit to operation with moving-bed reactors may include thereplacement or conversion of at least one fixed-bed reactor andpreferably all of the fixed bed reactors in the unit to moving-bedreactors. The catalyst facilities of the converted unit and thecontinuous moving-bed reactors will be operatively connected withexisting plant equipment, as necessary. The moving bed reactors may bedisposed in a side-by-side or stacked arrangement, depending on siterequirements. The conversion does require addition of catalyst loading,recovery (unloading) and transfer facilities associated with theinterface between the continuous reactor(s) and the regenerationfacilities which have been selected, that is, off-site, non-integratedon-site or partly integrated (shared regenerator) regeneration.

[0027] The spent catalyst recovered from the reforming unit may becollected and transferred to on offsite regeneration facility.Preferably the catalyst may be recovered in a continuous manner. Thespent catalyst that exits the last reactor will be collected in a spentcatalyst storage container and then transferred in smaller batches todrums or special containers suitable for transportation to an offsiteregeneration facility.

[0028] The catalyst may be collected in storage devices (drums,containers, vessels) and transferred to the regeneration facility. Thefacilities for collecting and transferring the spent catalyst maydiffer. For example, they could be as simple as a dump nozzle at thebottom of the last reactor emptying into conventional 200 litre (55 USgallon) drums. Alternatively, they could include specially designedtrucks, rail cars, or shipping containers capable of maintaining aninert atmosphere during loading, transportation and unloading.

[0029] The catalyst regeneration facility can be an offsite or an onsitefacility preferably centrally located if site conditions permit. In mostcases the regeneration facility will preferably be independent and onlyindirectly associated with a particular reforming unit although theshared regenerator configuration may be possible and even desirable incertain circumstances. Independent regeneration facilities will thusoperate autonomously from any particular reforming unit and mayregenerate catalyst from one or more reforming units. This will allowfor increased operational flexibility for the reforming units as well asthe regeneration facility, lower investment cost (on unit basis) andimproved reformate product. According to this embodiment a centrallylocated catalyst regeneration facility receives spent catalyst from aplurality of moving-bed reformers continuously or intermittently andsupplies the reactors of these units continuously or intermittently withregenerated catalyst.

[0030] Any typical reforming catalyst may be used, including thosecomprising one or more Group VIII noble metals on a refractory support.The catalyst will contain a hydrogenation-dehydrogenation function(hydrogen transfer) and an acid function. Examples include catalystscomprising platinum, tin, rhenium, iridium, tin or combinations of thesemetals. A preferred support includes substantially spherical aluminasupport particles. A preferred catalyst comprises platinum, platinum andtin, or platinum and rhenium on substantially spherical alumina supportparticles. Spherical particles are preferred for movement through themoving bed reactors and other equipment with minimal attrition.

[0031] Any type of regeneration facilities may be used. One preferredregeneration facility may include a continuous moving-bed regenerationtower characteristic of commercially available continuous reformingprocesses or it may include a batch regeneration process unit. Oneexample of a batch regeneration process is the Hot Flue Gas RegenerationCircuit characteristic of Cyclic POWERFORMING™. Another example is ashut down semiregenerative unit used exclusively for catalystregeneration.

[0032] A suitable regeneration procedure may include a hydrocarbonpurge, coke burn, oxy-chlorination, oxides purge, and reductionprocedure. However, depending on the type of catalyst it may alsoinclude presulfiding as part of the regeneration procedure. It may bepreferable to complete the reduction and presulfiding (if necessary)after the regenerated catalyst has been returned from the offsiteregeneration facility immediately before feeding the regeneratedcatalyst to the top of the lead reactor. The oxy-chlorination proceduremay vary significantly. At a minimum it may include the addition of achloride containing agent such as Cl₂, HCl, or a pumpable organicchloride after the coke burn to replace the chloride lost during thecoke burn. However, it may also include a continuous addition of achloride agent during the coke burn. It may also includeover-chlorination after the coke burn followed by a chlorideequilibration step after the platinum metal has been thoroughlyredispersed. The actual regeneration procedure might include anycombination of these chlorination techniques.

[0033]FIG. 1, given for example only, shows a continuous catalyticmoving-bed reforming process unit 10. This unit is built from anexisting high pressure semiregenerative reformer unit by removing thefixed bed reactor cases and installing moving bed cases which aredeployed in a side-by-side arrangement. If site requirements, forexample, limited area, dictate, a stacked reactor configuration couldwell be used with a consequent reduction in catalyst transfer equipmentas the lift pots and transfer lines shown in FIG. 1 could simply bereplaced by gravity trickle from one reactor to the next reactor in thetrain. In FIG. 1, thicker lining indicates new equipment and pipingwhile thinner lining indicates existing equipment and piping.

[0034] The conversion includes replacing each semiregenerative reactor(not shown) with a new moving-bed reactor 27, 57, 65, installing afresh/regenerated catalyst loading platform 18, a fresh catalyst storagedrum 20 which can be fed with fresh/regenerated catalyst through line 11with feed controlled by valve 13. Other newly added items include spentcatalyst storage drums 71 and 73, intra-unit catalyst transfer equipmentincluding collectors 24, 54, 64, lift pots 31, 61, 69 and transfer lines53, 58, 59, a spent catalyst loading platform 24, dust filters 26, a N₂cooler 28, a N₂ circulator 30, make-up nitrogen supply 32 and a H₂preheater 34. Similar facilities for unloading spent catalyst form thelast reactor are shown which include a disengaging hopper 71, lockhopper 73, and loading platform 74. Other additional items re discussedbelow. The following existing equipment items are retained and reused inthe converted unit: charge furnace 36, reheat furnaces 38, 40,feed/effluent heat exchanger 42 and associated lines, effluent cooler 44and associated lines, product separator 46, recycle compressor 48 andchloride treaters 50.

[0035] In operation the converted unit operates as follows:

[0036] Fresh catalyst or regenerated catalyst from the offsiteregeneration facility is placed on loading platform 18 and added to theregenerated catalyst storage drum 20. The catalyst then enters the lockhopper 17 where it is purged with nitrogen from line 15 to removeresidual air. The catalyst is then transferred to the lift engager 19where it is lifted with hydrogen gas fed through line 19 and valve 21 toreduction/purge/disengaging chamber 12 on top of first reactor 27 by wayof transfer line 52. Gas is removed from hopper 12 in elutriation tube12 and passes through line 43 to dust filters (new) 26. Reduced catalystis added to the first reactor 27 via catalyst flow lines 37. Catalystmoves by gravity downwards in reactor 27 until it exits through lines 41and enters catalyst collector 24 which is fed with hydrogen rich gasthrough line 39. Catalyst from catalyst collector 24 then enters liftengager 31 where it is lifted with a H₂ rich stream to disengaginghopper 55. Lift gas is admitted through valve/inlet 33. The catalystenters the second disengaging hopper 44 atop second reactor 57 afterwhich it enters reactor 57 where it moves downward to the outlet andpasses into catalyst collector 54, followed by lift engager 61. Catalystfrom lift engager 61 is then lifted with a hydrogen rich gas todisengaging hopper 16 atop third and last reactor 65 from which it thenpasses to the inlet of the third and last reactor 65. Catalyst flowsdownward through reactor 65 to collector 64 and then to lift engager 69.Catalyst from lift engager 69 is lifted with a hydrogen rich gas todisengaging/storage drum 71 in which gas is separated from the catalystand passes through elutriation tube 22 to dust filter 26. The spentcatalyst is then transferred to lock hopper 73 where it is purged withnitrogen and finally loaded into the shipping containers on SpentCatalyst Loading Platform 24.

[0037] The reformer charge enters the unit at inlet 85 and passesthrough line 82 picking up hydrogen rich recycle gas from line 83 toeffluent heat exchanger 42 and then to pre-heat furnace retained fromthe original unit. From pre-heat furnace it passes into contact with thecatalyst in first reactor 27. After passage through first reactor 27 itpasses in turn through re-heat furnace 38 (also a retained item) tosecond reactor 57, through reheat furnace 40 (retained) and finally tothird reactor 65. Reformate effluent from the third reactor is taken vialine 89 to charge heat exchanger 42 and recycle hydrogen heat exchanger34 to effluent cooler 44 and then via line 88 to the existing productseparator 46 in which liquid and as are separated. Hydrogen rich gas isrecompressed in compressor 48 fed through line 77 and passes either asrecycle gas through line 83 back to the unit or out through existingchloride treaters 50 to the refinery. Unstabilized reformate isrecovered through line 75.

[0038] Nitrogen for purge is introduced through make up inlet 32 andpasses to the nitrogen loop via knock out drum 45 and then through line51 to lift engager 17 with nitrogen also being introduced into lockhopper 23 through line 15. Gas from the reactors passes through the dustfilters 26 to nitrogen cooler 28 before returning to the nitrogen loopthrough knock out drum 45.

[0039]FIG. 1 does not depict the actual offsite or centrally locatedon-site regeneration facilities. Several different designs for theseregeneration facilities may be used. A preferred design is likely tovary based on the actual project specifics. Options for offsiteregeneration systems may include:

[0040] 1) facilities already available from commercial catalystregeneration companies;

[0041] 2) continuous moving-bed regeneration technology;

[0042] 3) commercially available cyclic regeneration facilitiesincluding Hot Flue Gas Technology offered by ExxonMobil POWERFORMINGTechnology; or

[0043] 4) idle existing semiregenerative catalytic reformer of variousconfigurations dedicated to completing catalyst regeneration.

[0044] Variations of the present method may include:

[0045] 1) sending all spent catalyst removed from the outlet of the lastreactor to a third party catalyst vendor who will regenerate thecatalyst for a fee;

[0046] 2) building an oversized regeneration facility as part of aconversion project for an existing semiregenerative reformer. Thefacility may be sized to regenerate catalyst from other units that mayalso be converted;

[0047] 3) build an oversized regeneration facility at some centrallocation and size it to regenerate catalyst from other semiregenerativereformers in the region that will be converted;

[0048] 4) use an existing idle semiregenerative reformer or move thoseidle facilities to some more appropriate location to regenerate thespent catalyst from other operating semiregenerative reformers in theregion that will be converted; and

[0049] 5) expand existing regeneration facilities at one or morelocations that already use continuous catalytic regeneration technologyso that the onsite facilities at that site (or sites) can alsoregenerate catalyst from other units (in addition to the catalyst thatthey currently regenerate from their own integrated unit).

EXAMPLE

[0050] Table 1 presents results of a feasibility study to evaluate theunit of FIG. 1. TABLE 1 Revamp with Semiregenerative Offsite ProcessRegeneration Before Revamp (FIG. 1) Feed Rate, m³/day (kbd) 4,770 (30)5,406 (34) Severity, RON 95 100 Reactor Pressure, kPag (psig) 3344 (485)2482 (360) C₅+ Yield, LV % 72.5 72.1 H₂ Production, n.l.l.⁻¹ (SCF/B) 77(435) 130 (733)

[0051] Reactor pressure is reduced about 25 percent, from 3344 to 2482kPag (485 to 360 psig) despite an increase in feed rate from 4,770 to5,406 m³/day (30 to 34 kbd). This reduction in reactor pressure allowsthe refiner to maintain a relatively constant C₅+ reformate yielddespite a severity increase from 95 to 100 RON. Hydrogen production alsoincreases by almost 70% from 77 to 130 n.l.l.⁻¹ (435 to 733 scf/B).

[0052] Catalyst regeneration facilities may be used to regenerate spentcatalyst from more than one reformer, thus achieving economies of scaleand (2) to achieve somewhat more modest pressure reductions and yieldimprovements, but at a significantly lower project investment thanexisting conversions with dedicated continuous catalyst regenerationfacilities.

1. A method for the conversion of a fixed-bed catalytic reformer unit tomoving bed reactor operation, the method comprising: converting at leastone fixed bed reforming reactor of a fixed-bed catalytic reformer unithaving at least one fixed-bed catalytic reformer reactor to a moving-bedcatalytic reformer reactor that allows continuous or intermittentaddition of freshly regenerated catalyst to a catalyst inlet of themoving-bed reactor and continuous or intermittent removal of spentcatalyst from a catalyst outlet of the moving-bed reactor; addingcontinuous or intermittent catalyst feeding facilities at the catalystinlet of the moving bed reactor for charging fresh or regeneratedcatalyst continuously or intermittently to the continuous moving-bedreactor through the catalyst inlet; adding spent catalyst recoveryfacilities for collecting the spent catalyst from the catalyst outlet ofthe moving bed reactor, and transferring the spent catalyst to areforming catalyst regeneration facility which is not integrated withthe reactor from which the catalyst is removed; operating the moving-bedreactor at an effective pressure to improve reformate quality and yieldrelative to those of the reformate product from the fixed-bed unitbefore the conversion; removing continuously or intermittently spentcatalyst from the moving-bed reactor; and transferring it to thenon-integrated regeneration facility.
 2. The method of claim 1, in whichthe regeneration facility is a community onsite regeneration facilityfor a plurality of reforming units and in which the community onsiteregeneration facility receives spent catalyst from the plurality ofreforming units continuously or intermittently, regenerates the spentcatalyst and supplies continuously or intermittently the plurality ofreforming units with regenerated catalyst.
 3. The method of claim 1, inwhich the regeneration facility is an off-site regeneration facilityadapted to regenerate spent catalyst from a plurality of reformingunits.
 4. The method of claim 1, in which the regeneration facility is amoving bed regenerator integrated with a second moving bed reformer unitand of a capacity which enables it to accept the catalyst from themoving bed reactor of the converted unit after conversion.
 5. The methodof claim 1, in which the fixed bed reforming unit includes a pluralityof fixed bed reactors connected in a series train for reformer chargeflow from one reactor to the next in the train, each of which isconverted to a moving bed reactor connected in a series train forreformer charge flow and for reforming catalyst flow from one reactor tothe next in the train.
 6. The method of claim 5 in which the catalystflow in the reactor train is cocurrent with catalyst flow in the reactortrain.
 7. The method of claim 1 in which the moving bed reactor isoperated after the conversion at a pressure lower than the pressure ofthe fixed bed reactor before conversion.
 8. The method of claim 7 inwhich the fixed bed reactor is operated before the conversion at apressure of 1035 to 3800 kPag and the moving bed reactor is operatedafter conversion at a pressure which is within the range of 345 to 2760kPag and at a value which is lower than that of the fixed bed reactorbefore conversion.
 9. The method of claim 8 in which the moving bedreactor is operated at a pressure of 690 to 2620 kPag after conversion.10. The method of claim 9 in which the moving bed reactor is operated ata pressure of 1035 to 2415 kPag after conversion.
 11. The method ofclaim 7 in which the moving bed reactor is operated after the conversionat a pressure which is equal to 20 to 60 percent lower than the pressurewithin the range of 1035 to 3800 kPag at which the fixed bed reactor isoperated before the conversion.
 12. The method of claim 11 in which themoving bed reactor is operated after the conversion at a pressure whichis equal to 25 to 50 percent lower than the pressure within the range of1035 to 3800 kPag at which the fixed bed reactor is operated before theconversion.
 13. The method of claim 1, in which the fresh or regeneratedcatalyst comprises one or more Group VIII noble metals on a refractorysupport.
 14. The method of claim 1, in which the fresh or regeneratedcatalyst comprises a hydrogenation-dehydrogenation function and an acidfunction.
 15. The method of claim 1, in which the fresh or regeneratedcatalyst comprises platinum, tin, rhenium or combinations thereof on asubstantially spherical alumina support particle.
 16. The method ofclaim 1, in which the fresh or regenerated catalyst comprises platinum,platinum and tin, or platinum and rhenium on substantially sphericalalumina support particles.
 17. The method of claim 1, in which thecatalyst feeding facility is operatively connected with the moving-bedcatalytic reformer reactor; the catalyst recovery facility isoperatively connected with the moving-bed catalytic reformer reactor andthe catalyst feeding facility, the catalyst recovery facility and themoving-bed catalytic reformer reactor are operatively connected withexisting fixed-bed unit facilities including reforming charge heatersand reformate product recovery facilities retained from the fixed bedunit.
 18. A method for the conversion of a fixed-bed catalytic reformerunit to moving bed reactor operation, the method comprising: convertingat least one fixed bed reforming reactor of a fixed-bed catalyticreformer unit having at least one fixed-bed catalytic reformer reactorhaving an operating pressure of from 1035 to 3800 kPag to a moving-bedcatalytic reformer unit having at least one moving bed reactor, the unithaving catalyst feeding facilities that allow continuous or intermittentaddition of freshly regenerated catalyst to a catalyst inlet of themoving-bed reactor and continuous or intermittent removal of spentcatalyst from a catalyst outlet of the moving-bed reactor; addingcontinuous or intermittent catalyst feeding facilities at the catalystinlet of the moving bed reactor for charging fresh or regeneratedcatalyst continuously or intermittently to the continuous moving-bedreactor through the catalyst inlet; adding spent catalyst recoveryfacilities for collecting the spent catalyst from the catalyst outlet ofthe moving bed reactor, and transferring the spent catalyst to areforming catalyst regeneration facility which is not integrated withthe reactor from which the catalyst is removed; operating the moving-bedreactor at an effective pressure from 20 to 50 percent lower than theoperating pressure of the fixed bed reactor to improve reformate qualityand yield relative to those of the reformate product from the fixed-bedunit before the conversion; removing continuously or intermittentlyspent catalyst from the moving-bed reactor; and transferring it to thenon-integrated regeneration facility.
 19. The method of claim 18 inwhich the fixed bed reforming unit includes a plurality of fixed bedreactors which are converted to a plurality of moving bed reactorsoperating at a pressure of 345 to 2760 kPag and lower than the operatingpressure of the fixed bed reactors.
 20. A method for the conversion of afixed-bed catalytic reformer unit to moving bed reactor operation, themethod comprising: converting at least the reactors of a fixed-bedcatalytic reformer unit having a plurality of sequential fixed-bedcatalytic reforming reactors to a moving-bed catalytic reformer unitwith a plurality of sequential moving bed reforming reactors; addingcontinuous or intermittent catalyst feeding facilities at the catalystinlet of the first moving bed reactor in the sequence of moving bedreactors for charging fresh or regenerated catalyst continuously orintermittently to the continuous moving-bed reactor through the catalystinlet; adding spent catalyst recovery facilities for collecting thespent catalyst from the catalyst outlet of the last moving bed reactorin the sequence of moving bed reactors, and transferring the spentcatalyst to a reforming catalyst regeneration facility which comprises areforming catalyst regenerator which is integrated with a second movingbed catalytic reforming unit but is not integrated with the moving bedreactor from which the catalyst is removed; operating the moving-bedreactor at an effective pressure within the range of 345 to 2760 kPagand lower than the operating pressure of the fixed bed reactors beforeconversion to improve reformate quality and yield relative to those ofthe reformate product from the fixed-bed unit before the conversion;removing continuously or intermittently spent catalyst from the lastmoving-bed reactor in the sequence; and transferring it to theregenerator, regenerating the catalyst in the regenerator and returningregenerated catalyst to the first moving bed reactor of the sequence ofmoving bed reactors in the converted unit.